prevent large files from being cached in memory (backups!)

nocache <I/O-heavy-command>
We all know... nice -n19 for low CPU priority.   ionice -c3 for low I/O priority.   nocache can be useful in related scenarios, when we operate on very large files just a single time, e.g. a backup job. It advises the kernel that no caching is required for the involved files, so our current file cache is not erased, potentially decreasing performance on other, more typical file I/O, e.g. on a desktop.   http://askubuntu.com/questions/122857 https://github.com/Feh/nocache http://packages.debian.org/search?keywords=nocache http://packages.ubuntu.com/search?keywords=nocache   To undo caching of a single file in hindsight, you can do cachedel <OneSingleFile>   To check the cache status of a file, do cachestats <OneSingleFile>

What Others Think

Damn, that's useful!
flatcap · 286 weeks and 2 days ago
+1
wejn · 286 weeks and 1 day ago
For those on Ubuntu Precise, I have a backport of nocache in my PPA: https://launchpad.net/~fmarier/+archive/ppa/+index?field.series_filter=precise&batch=75&memo=75&start=75
fmarier · 284 weeks ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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